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Trigger Pull

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Trigger Pull

There are three commonly used methods to determine trigger pull:

  • Trigger weights
  • Spring scale
  • Digital scale

Laboratory protocols may determine the method that should be used to measure trigger pull.

When testing the trigger pull of a revolver, each chamber of the cylinder should be measured, noting any variations.


Trigger Weights

Revolver in position on trigger weights
Revolver in position on trigger weights
Courtesy of St. Petersburg College Firing Range (see reuse policy).

Trigger weights are the most commonly used method of determining trigger pull. The system consists of a shaped rod and different sizes of metal weights (usually , , 1, 2, and 5 pounds) placed on a flat surface (rest).

The steps in measuring trigger pull with trigger weights are as follows:

  1. For single-action trigger pull, cock the firearm. For double-action trigger pull, do not cock the firearm.
  2. Place the trigger under the top portion of the rod.
  3. Slowly lift the firearm upward with the rod, bringing force on the trigger.
    1. If the weights come off the rest without the firearm discharging, add more weight to the rod.
    2. If the firearm discharges before the weights come off the rest, remove weight from the rod.
  4. Continue until the least weight required to cause the firearm to discharge without the weights leaving the rest is determined.



Trigger pull spring scale
Trigger pull spring scale
Courtesy of Cabela's (see reuse policy).

The steps in measuring trigger pull with a spring scale are the following:

  1. Cock the firearm.
  2. Attach one end of the scale to a fixed object and position the other end against the trigger.
  3. Slowly pull away from the fixed object until the firearm discharges.
  4. Record the pounds of pressure required to discharge the firearm as indicated on the scale.
Trigger pull digital scale
Trigger pull digital scale
Courtesy of Cabela's (see reuse policy).

Digital trigger pull scales operate in a similar way to spring scales. Calibrate and use digital scales as specified by manufacturers instructions.


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